1. Field of the Invention
The present invention relates, in general, to air filters, and in particular to an air filter for use in heating, ventilating, cooling, and forced air systems
2. Information Disclosure Statement
There are typically relatively few popular sizes, e.g., five, of air filters used in homes and the like. On the other hand, there is a need for many different odd size filters. The problem generally occurs when contractors build a house. Rather than building the opening for the filter a standard size, a great many of the contractors will cut the size hole for whatever is convenient for them to cut. There are adjustable frames on the market in which one channel is telescopically received within another which may be relevant prior art to the present invention. However, none of these frames are completely satisfactory for one reason or another, for example, the telescoping channels are flimsy and difficult to assemble.
It is, therefore, desirable to have an air filter which is sturdy and easy to assemble.
A preliminary patentability search in Class 55, subclasses 501, 496, 503, 506, 511, 516, 481, 482 and digest 31, and Class 160, subclasses 372, 373 and 374, produced the following patents, some of which may be relevant to the present invention: Sweeney, U.S. Pat. No. 1,122,437, issued Dec. 29, 1914; Lichtman, U.S. Pat. No. 2,175,903, issued Oct. 10, 1939; Lewis, U.S. Pat. No. 2,802,544, issued Aug. 13, 1957; Bell, U.S. Pat. No. 3,274,759, issued Sept. 27, 1966; Weed, U.S. Pat. No. 3,675,402, issued Jul. 11, 1972; and Pick, U.S. Pat. No. 5,059,218, issued Oct. 22, 1991.
While each of the above patents disclose various filters and screens, none disclose or suggest the present invention. More specifically, none of the above patents disclose or suggest an air filter for use in heating, ventilating, cooling, and forced air systems in which an adjustable frame formed of a material adapted to be cut by a cutting device comprises at least one female section having at least one leg; at least one male section having at least one leg telescopingly mated with said female section; coacting means on said leg of said female section and on said leg of said male section for permitting lengthwise telescoping movement of said leg of said male section and said leg of said female section relative to one another and yet preventing inward separation of said leg of said female section from said leg of said male section; and locking means for locking said leg of said female section and said leg of said male section in a fixed assembled position relative to one another.
Sweeney, U.S. Pat. No. 1,122,437 discloses a screen that is adjustable in one direction to fit a window. The end portions of the screen are provided with dovetailed tongues which can be gripped by the end portions of the side strips.
Lichtman, U.S. Pat. No. 2,175,903 discloses an adjustable air filter which may be adjusted as to size and attached to various types of hot air registers in homes, offices, and other buildings. The frame is made of four L-shaped sections formed as channel members which telescope with adjacent channel members. There are wing screws to hold the telescoping sections in predetermined positions. The sections are provided with barbs intended to permit the filter element t be impaled thereon.
Lewis, U.S. Pat. No. 2,802,544 discloses a filter screen for fluids wherein the filtering medium is a brush or a plurality of brushes. The filter has a four sided rectangular metal frame with each side being in the form of a channel. The filter screen further comprises rectangular front and rear sheets of expanded metal. The assembly is held in place within the frame by four clamping plates having wing nuts for holding the clamping plates in position.
Bell, U.S. Pat. No. 3,274,759 discloses an adjustable frame structure for air filters and the like adapted for use as window screens or ventilators. The adjustable frame structure includes a first and second generally rectangular frame with each frame including a pair of rails and a pair of end-frame members. Each of the rails has a key-retaining guideway therein. One end frame member of each of the frames has a pair of key members slidably retained in the guideway of the other frame and longitudinally slidable to hold the two frames in confronting, overlapping slidable relationship.
Weed, U.S. Pat. No. 3,675,402 discloses an adjustable filter assembly adapted to be inserted in apertures of buildings such as windows or doors or the like. The frame assembly is telescopically adjustable in two different directions and is provided with a clamp for holding the adjustment at any desired predetermined size or shape within the confines of its adjustment limits.
Pick, U.S. Pat. No. 5,059,218 discloses a construction for supporting a flexible screen or sheet such as a window screen, or the like, and its application to the assembly of an electrostatic air filter of the charged media type. The filter includes a U-shaped channel adapted to receive a spline member for frictionally engaging a flexible sheet such as a window screen.